31963942081 has 2 divisors, whose sum is σ = 31963942082. Its totient is φ = 31963942080.

The previous prime is 31963942067. The next prime is 31963942103. The reversal of 31963942081 is 18024936913.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20057640625 + 11906301456 = 141625^2 + 109116^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31963942081 is a prime.

It is a super-2 number, since 2×31963942081² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31963942001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15981971040 + 15981971041.

It is an arithmetic number, because the mean of its divisors is an integer number (15981971041).

Almost surely, 2^31963942081 is an apocalyptic number.

It is an amenable number.

31963942081 is a deficient number, since it is larger than the sum of its proper divisors (1).

31963942081 is an equidigital number, since it uses as much as digits as its factorization.

31963942081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 279936, while the sum is 46.

The spelling of 31963942081 in words is "thirty-one billion, nine hundred sixty-three million, nine hundred forty-two thousand, eighty-one".